Seiko Cal. 6635 - 521

The Seiko 6635-521 represents an important milestone in Seiko's 1973 lineup. Powered by the 6635 caliber with 25j jewels beating at 21,600 bph, it delivers a 48 hours power reserve. [seikata-wm-bc02b2125e49]

Also known as: UFO

Specifications

Movement

Spring Drive

Case Material

Titanium

Case Width

46mm

Case Thickness

15.4mm

Lug Width

18mm

Crystal

Acrylic

Bezel

Fixed

Water Resistance

80m

Dial Color

White

Jewels

25j

Frequency

21,600 bph

Power Reserve

48 hours

Year

1973

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